Welcome to the FicoForums,
@JohnD, and good question. It'll highly depend on your own situation + financial goals.
I'll say that one can keep it ultra-simple by considering what part of a full budget matters the most to you: total discretionary spend? reducing spend in a certain category? paying down high-interest debt (CCs)? low-interest debt (auto)? Saving into CD/Brokerage accts?
You can easily set own your own Excel budget tool to satisfy 1 (or more) of the above goals. If the $ amount of spend/debt seems overwhelming, consider budgeting only in terms of percentages (%) of your take-home pay.
I am halfway an Excel guru, so I like developing my own number-crunching tools. For example, I am currently in a situation where I'd like to reduce my total discretionary spend to a certain $ amount per month...so I insert + categorize all transactions (of 4 categories) monthly and Excel outputs the spend per category. I also allocate where my take-home pay is going $Dollar-wise before I get paid, so I can rapid-fire transfers from checking on pay day.
Interested to see what other FF users do